EEUURROOHHEEAATTIIMMPPRROOVVIINNGG PPUUBBLLIICC HHEEAALLTTHHRREESSPPOONNSSEESS TTOO EEXXTTRREEMMEEWWEEAATTHHEERR//HHEEAATT--WWAAVVEESS

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EEUURROOHHEEAATTIIMMPPRROOVVIINNGG PPUUBBLLIICC HHEEAALLTTHHRREESSPPOONNSSEESS TTOO EEXXTTRREEMMEEWWEEAATTHHEERR//HHEEAATT--WWAAVVEESS

For further information on the EuroHEAT project, see the WHORegional Office for Europe(http://www.euro.who.int/globalchange/Topics/20050524_2)or contact:Bettina MenneWHO Regional Office for EuropeTel.: +39 06 487751E-mail: globalchange@ecr.euro.who.int

World Health Organization Regional Office for Europe Scherfigsvej 8, DK-2100 Copenhagen Ø, Denmark Tel.: +45 39 17 17 17. Fax: +45 39 17 18 18 E-mail: postmaster@euro.who.int Web site: www.euro.who.int <file://www.euro.who.int> ––––––––––––––––––––––––––––––––––––––––––––––––––––––© World Health Organization 2009All rights reserved.

EuroHEAT, a project coordinated by the WHO Regional Office forEurope and co-funded by the European Commission (EC) Directorate-General for Health and Consumers (DG SANCO), has quantified thehealth effects of heat in cities in the WHO European Region and hasidentified options for improving the preparedness of health systemsand their responses to protect health. The project contributed to theimplementation of the commitments specified in the Declaration ofthe Fourth WHO Ministerial Conference on Environment and Health(identifying, mitigating, preventing and adapting to the healthimpacts of climate change and taking action to reduce the currentburden of disease due to extreme weather and climate events) and inthe EC environment and health action plan. The EuroHEAT team wascomposed of representatives from 7 European scientific institutionsand was supported by an advisory committee of 19 experts from 14countries and the EC.

Heat threatens health.

Climate change increases heat-waves.

Can the health effects

of hot weather be prevented?

What public health strategies and measures

can be adopted?

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Despite the greenhouse-gas mitigation policies that are now being implemented inEurope, some degree of global climate change is thought to be inevitable. As aresult, heat-waves are projected to increase in number, intensity and duration overmost land areas in the 21st century1. This trend will increase the risk of heat-relatedmortality and morbidity, especially for elderly, chronically ill, very young and sociallyisolated individuals. More than 44 000 additional deaths were recorded in August2003 in 12 European countries2. A ten-year analysis in 15 European cities, carriedout by the project on the assessment and prevention of acute health effects ofweather conditions in Europe (PHEWE), estimated a 2% increase in mortality innorthern cities and a 3% increase in southern cities for every 1 °C rise in apparenttemperature3 above the city threshold level4. The aim of EuroHEAT was to improvepublic health responses to weather extremes and in particular heat-waves.

Heat threatens health. Hot weather can cause illness and kill.

What is a heat-wave and how does it affect health?There is no standard definition for a heat-wave. EuroHEAT defined a heat-wave as“a period where the maximum apparent and the minimum temperature are overthe 90th percentile of the monthly distribution for at least two days”. Long and intense heat-waves are more deadly. In the nine European cities analysedby EuroHEAT (Athens, Barcelona, Budapest, London, Milan, Munich, Paris, Romeand Valencia), the estimated increase in mortality ranged from 7.6% to 33.6%during heat-wave episodes. The impact of longer heat-waves (more than four days)on mortality was 1.5-5 times higher than that of short heat-waves.

1 IPCC (2007). Summary for policymakers. In: Parry ML et al., eds. Climate change 2007: impacts, adaptation and vulnerability. Contribution ofWorking Group II to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change. Cambridge, Cambridge University Press:7–22.

2 Robine J-M et al. (2008). Death toll exceeded 70 000 in Europe during the summer of 2003. Comptes Rendus Biologies, 331(2): 171–178.3 Apparent temperature is a measure of relative discomfort due to combined heat and high humidity, developed on the basis of physiological studies

on evaporative skin cooling. It can be calculated as a combination of air temperature (Temp) and dew point (Dew) in °C.4 Baccini M et al. (2008). Effects of apparent temperature on summer mortality in 15 European cities: results of the PHEWE project. Epidemiology,

19(5): 711–719.

5 With a diameter under 10 µm.

The combined effect of heat-waves and peaks of ozone or fine particulatematter (PM10)5 air pollution increases mortality.

There is growing evidence from EuroHEAT that the effects of heat-wave days onmortality are larger when levels of ozone or PM10 are high, particularly among theelderly (75–84 years). The total daily number of deaths in this age group increasedby 16.2% on heat-wave days with high ozone levels and by 14.3% on days withhigh PM10 levels, respectively, compared to an increase of 10.6% and 10.5% ondays with low levels of ozone and PM10. Future heat-wave studies thus need toadjust their estimated effects for air pollution levels. The mortality increase due tothe combined effect of heat and air pollution can be reduced by decreasingexposure to PM10 and ozone on hot days.

Some people are less able to cope with heat stress than others.

A wide range of chronic diseases (including being confined to bed) and medicaltreatments, social isolation and some types of occupation increase the risk of heatstress in individuals.Across Europe, housing and socioeconomic conditions show varying influence onthe impact of heat on health. In European cities, the elderly suffer the greatesteffects of heat-waves, with more women dying than men.Public health interventions need to identify and target particularly vulnerablepopulation groups and individuals.

Heat-related deaths are expected to grow as a consequence of projectedincreases in heat-wave frequency, intensity and duration, due to climatechange.

For 2030, under a high carbon dioxide (CO2) emission scenario more than 400deaths per year due to high temperatures are expected, for example for each of thefollowing cities: Athens, Paris, Rome and Budapest.

Heat–health action plans help prevent the adverse health effects ofheat-waves.

The adverse health effects of heat-waves are largely preventable.EuroHEAT recommends the development and implementation of heat–healthaction plans at national and regional level in Europe, to prevent, react to andcontain heat-related risks to health.

As part of EuroHEAT, the German Weather Service has developed an online toolproviding medium-term forecasting of heat (http://www.euroheat project.org/dwd).This tool, which maps the probability of a forthcoming heat-wave, can supporthealth services in planning and in taking decisions.

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Eight steps to build a heat–health action plan

1 Collaboration between bodies and institutions and identification of alead body to coordinate responsesThis includes the definition of roles and responsibilities for actors at thenational/regional level. Exploration of financial incentives, legislation andsynergies with the International Health Regulations (2005) and existing nationaldisaster plans is advised.

2 Availability of accurate and timely alert systemsHeat-health warning systems (HHWS) should be developed in collaboration withmeteorological services to trigger warnings, determine the threshold for actionand communicate the risks. An HHWS can use various methods for forecastingand an effective system is targeted to local needs and is accurate and timely.Experiences of various countries should be shared.

3 Heat-related health information developed in advanceAs heat-waves are likely to occur every summer, although in different locationsin Europe, it is advisable to establish a communication plan before the summer.This plan should include advice to people on how to protect oneself and others,how to reduce heat exposure indoors and outdoors and how to recognize heat-related symptoms. Information targeted at particular groups, such as healthcare institutions and caregivers, should also be provided.

4 Avoidance or reduction of heat exposureAs part of the plan, measures to reduce exposure should be taken, such asadaptation of individual behaviour, short-, medium- and long-term measures inbuildings to reduce indoor temperatures and long-term improved urbanplanning, building design, transport and energy policies. Medium- and short-term options are available for cooling buildings without power consumption(passive cooling), such as cool paints, external shading, radiant barriers andinsulation of buildings. Advice should be given to the public on how best toreduce indoor temperatures, with particular attention to avoiding pollutants.Possible electricity shut-offs and reduced water availability need to beconsidered in heat–health action plans and public advice.

5 Particular care for vulnerable population groupsIt is helpful to identify groups at high risk before the summer and to plan andtarget interventions (advice, follow-up and care) accordingly. Communityorganizations, medical practitioners and care providers play an important role.

6 Provision of health care, social services and infrastructureThis includes summer health workforce planning, health service provision andtraining of health personnel and other interest groups. It is advisable that carehomes and hospitals meet the European Union criteria for the thermal indoorenvironment to prevent heat-related illness in patients and staff. Emergencydepartments of hospitals could be alerted to heat-waves to better manage anincrease in patient admissions.

7 Real-time health surveillance incorporated into the planning processReal-time surveillance is important to detect early impacts of hot weather, topotentially modify interventions and to inform about abnormal outbreaks orclusters of health impacts. The most useful real-time data are all-cause mortality,emergency calls, emergency department visits, hotlines and general practitionerrecords. They should be available within a maximum of one to two days.

8 Monitoring and evaluation components and criteriaIt is crucial at the end of the summer to evaluate whether the heat–healthaction plan has worked according to defined process and outcome criteria.Monitoring health outcomes over time in relation to heat-waves is anotherimportant component of the plan.

For details please consult theGuidance for heat–health action planson the WHO Regional Office for Europe web site (www.euro.who.int/InformationSources/Publications/Catalogue/20080522_1)

The WHO Regional Office for Europe supports its Member States in thedevelopment and implementation of heat–health action plans.It is ready to assist authorities in preventing the adverse health effects of heat-wavesby providing:

• technical advice; • support for strengthening surveillance systems to better describe climate-related

health effects;• valid and reliable evidence on heat-related mortality and morbidity;• guidance for the definition of criteria for triggering heat–health interventions;• options for heat–health preparedness and response;• information exchange on monitoring and evaluation of public health

interventions in the framework of heat–health action plans.

Acknowledgements

Thanks to Antonis Analitis (University of Athens,

Greece), Paul Becker (German Weather Service,

Freiburg, Germany), Roberto Bertollini (WHO

headquarters, Geneva, Switzerland) Daniela

D’Ippoliti (Health Authority Rome-E, Rome, Italy),

Shakoor Hajat (London School of Hygiene and

Tropical Medicine, United Kingdom), Simon Hales

(University of Otago, Wellington, New Zealand),

Klea Katsouyanni (University of Athens, Greece),

Ursula Kirchmayer (Health Authority Rome-E,

Rome, Italy), Kriszta Kishonti (National Institute of

Environmental Health, Budapest, Hungary),

Christina Koppe (German Weather Service,

Freiburg, Germany), Sari Kovats (London School of

Hygiene and Tropical Medicine, United Kingdom),

Franziska Matthies and Bettina Menne

(Noncommunicable Diseases and Environment,

WHO Regional Office for Europe), Glenn McGregor

(The University of Auckland, New Zealand), Paola

Michelozzi (Health Authority Rome-E, Rome, Italy),

Anna Páldy (National Institute of Environmental

Health, Budapest, Hungary), Christian Schweizer

and Tanja Wolf (Noncommunicable Diseases and

Environment, WHO Regional Office for Europe),

Charlotte Huntly (Ironbridge, United Kingdom) and

Cristiana Salvi and Nicoletta di Tanno (Partnership

and Communications, WHO Regional Office for

Europe), as well as the members of the advisory

committee: Hugh Ross Anderson (St George’s

Hospital Medical School, London, United

Kingdom), Gilles Berrut (University of Angers,

France), Luigi Bisanti (Local Health Authorities

Milan, Italy), Arieh Bitan (University of Tel Aviv,

Israel), Abderrezak Bouchama (King Faisal Specialist

Hospital and Research Centre, Riyadh, Saudi

Arabia), Neus Cardeñosa Marín (Public Health

Directorate Catalonia, Barcelona, Spain),

Annamaria De Martino (Ministry of Health, Rome,

Italy), Henrieta Gajdosova (Public Health Authority

of the Slovak Republic, Bratislava, Slovakia), Giulio

Gallo (DG SANCO, European Commission,

Luxembourg), Irina Gudaviciene (Health Emergency

Situations Centre, Vilnius, Lithuania), Juhani Hassi

(University of Oulu, Finland), Gerd Jendritzky

(Meteorological Institute, University of Freiburg,

Germany), Giovanni Leonardi (Health Protection

Agency, Chilton, United Kingdom), Peter Otorepec

(National Institute of Public Health, Ministry of

Health, Ljubljana, Slovenia), Carlo A. Perucci

(Health Authority Rome-E, Rome, Italy), Günther

Pfaff (Landesgesundheitsamt, Stuttgart, Germany),

Antonio Tavares (National Institute of Health

Doctor Ricardo Jorge, Lisbon, Portugal) and Fritz

Wagner (Ministry for Health and Women, Vienna,

Austria). Cover picture: Elis Martinelli

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EEUURROOHHEEAATTIIMMPPRROOVVIINNGG PPUUBBLLIICC HHEEAALLTTHHRREESSPPOONNSSEESS TTOO EEXXTTRREEMMEEWWEEAATTHHEERR//HHEEAATT--WWAAVVEESS

SSuummmmaarryy ffoorr PPoolliiccyy––MMaakkeerrss

EEUURROOHHEEAATTIIMMPPRROOVVIINNGG PPUUBBLLIICC HHEEAALLTTHHRREESSPPOONNSSEESS TTOO EEXXTTRREEMMEEWWEEAATTHHEERR//HHEEAATT--WWAAVVEESS

For further information on the EuroHEAT project, see the WHORegional Office for Europe(http://www.euro.who.int/globalchange/Topics/20050524_2)or contact:Bettina MenneWHO Regional Office for EuropeTel.: +39 06 487751E-mail: globalchange@ecr.euro.who.int

World Health Organization Regional Office for Europe Scherfigsvej 8, DK-2100 Copenhagen Ø, Denmark Tel.: +45 39 17 17 17. Fax: +45 39 17 18 18 E-mail: postmaster@euro.who.int Web site: www.euro.who.int <file://www.euro.who.int> ––––––––––––––––––––––––––––––––––––––––––––––––––––––© World Health Organization 2009All rights reserved.